Natural greenhouse effect

Roughly 30% of incoming sunlight is reflected back into space by bright surfaces like clouds and ice. Of the remaining 70%, most is absorbed by the land and ocean.

The portion of the Sun's radiant energy that is not absorbed, scattered, or reflected (about 47%) passes through the Earth's atmosphere and warms its surface. Some of this energy is absorbed by naturally-occurring gases, including water vapour, carbon dioxide, methane, nitrous oxide, and ozone, which radiate the energy in all directions, including back to the Earth's surface.

This absorption and radiation of heat by the atmosphere - the natural greenhouse effect -is beneficial for life on Earth. If there were no greenhouse effect, the Earth’s average surface temperature would be a very chilly -18°C (0°F) instead of the comfortable 15°C (59°F) that it is today.

Exercise 9. Choose one topic from the Category of greenhouse gases and prepare a report.

http://en.wikipedia.org/wiki/Category:Greenhouse_gases

Unit Thirteen Effects of global warming

Exercise 1. Train the reading of the following words.

permeate, expansion, precipitation, glaciers, meters, predictions, anywhere, expansion, circulation, potentially, additionally, serious, approximately, quarter, decades, bleaching, weakens, ability, severe weather, frequent, evaporation, eventually, precipitation, further, flooding, drought, intensifying, unsuitable, previously, therefore, occur, usefulness, counterbalance, desertification, species, migration, hibernation, extinction, accustomed, penguins, further, native habitat, accommodating.

Exercise 2. Guess the meaning of the words without a dictionary.

continent, aspect, expansion, precipitation, meter, leader, circulation, potentially, serious, coral reef, decade, region, intensify, tropics, farming, pattern, migration, adaptation, arctic, polar, penguins, migratory.

Exercise 3. Read and translate the text. Divide the text into the meaningful parts and give them titles. Choose an abstract of ten lines and get ready to read it aloud.

The likely effects of global warming will not be limited to one country or even one continent and will permeate almost every aspect of the environment. Rising sea levels are the most common concern; taking place with a thermal expansion of the oceans, increased precipitation, and the melting of mountain glaciers. In the 20th century alone, sea levels rose 0.17 meters predictions for the next century range anywhere from 0.18 to 0.59 meters. Currently, the Arctic summer sea ice is about half as thick as it was in 1950. The melting Arctic sea ice does not contribute to sea-level rise, except for the expansion of seawater with increasing heat. However, melting Arctic sea ice may lead to global changes in ocean circulation. Water from melted ice forms a layer at the sea surface that is less dense than the underlying water since it is less salty, potentially preventing the pattern of deep ocean currents from rising to the surface. Additionally, melting sea ice speeds up the warming of the Arctic. Increasing ocean temperatures could cause serious ecological damage. Approximately one quarter of the world's coral reefs have died over the last few decades, many of them affected by coral bleaching - a process directly tied to warming waters which weakens the coral animals. An increase in global temperature will likely enhance the ability for severe weather, which could mean stronger and more frequent storms. Warmer temperatures cause more evaporation of water, which, as part of the water cycle eventually leads to increased precipitation and further increasing the potential for flooding. With drought affecting some regions and heat intensifying in the tropics, many areas will become unsuitable for agriculture. In tropical areas that are already dry and hot, the ability to harvest food will likely decrease even with small increases in warming. However, warmer temperatures and increased precipitation can also make previously poor land more suitable for farming. Therefore with a changing climate, a global change in the agricultural pattern will occur. Yet, it is unknown if the increase in the usefulness of poor lands will counterbalance an increase in drought and desertification. Many species are affected by global warming, most often by changes in migration patterns, shorter hibernation times, relocation to new areas, and extinction due to lack of adaptation. For example, many animals accustomed to living in the arctic regions, such as polar bears and penguins, have been forced further out of their native habitat in search of more accommodating habitat closer to the poles. Animals that migrate, such as birds and butterflies, have begun extending their migratory range closer to the poles, arriving sooner and departing later.

Exercise 4. Correct false statements, according the information from the text.

1. Almost all coral reefs have died over the last year, affected by coral bleaching.

2. Water of ocean currents is less salty and so may prevent water from melted ice from rising to the upper layers of ocean.

3. Many areas will become suitable for agriculture due to drought and hot weather.

4. An increase in global temperature will likely enhance the ability for stronger and more frequent storms.

5. Warmer temperature produces evaporation of water and decreases the possibility of drought.

6. Global warming will affect only few regions.

7. The melting of Arctic ice concerns only Arctic sea.

8. Water from melting ice slows down warming of the Arctic.

Exercise 5. Make sentences from the following letters.

1. Urbanizationandindustrializationalsoresultinlandpollution.

2. Roadscausevisualnoiselightairandwaterpollution.

3. Theconsequenceofintensiveagricultureismovetomonoculture.

4. Pesticideisasubstanceormixtureofsubstancesusedtokilla pest.

5. Thepurposeoftillageistopreparethesoilforgrowingcrops.

6. Humusisorganicmaterialinthefinalstagesofdecomposition.

7. allsoilorganismsdependonorganicmatterastheirfoodsource.

8. Twoimportantcharacteristicsofsoilaretextureandstructure.

9. Irrigationmaybedefinedasscienceofapplicationofwatertosoil.

10. Waterpollutionaffectsplantsandorganismslivinginwater.

Exercise 6. Tell in English what the following words and phrases mean.

global warming, environment, expansion, glacier, prediction, ecological damage, coral reefs, severe weather, storm, evaporation, flooding, drought, agriculture, desertification, species, migration, extinction, the Arctic, tropics.

Exercise 7. Make up sentences with the given words and phrases.

effects of global warming, environment, melting, sea-level rise, expansion, global changes, prevention, to cause ecological damage, evaporation of water, deforestation, acid rain, extinction of animals, solid waste, polluted air, to treat soil, fertilizer, changing climate, ecosystem, food chain, wastewater.

Exercise 8. Read the words, say which part of speech they belong to and translate them into Russian.

globe, global, globally; warm, warmly, warmer, warming; permit, permissive, permission; place, placement; expand, expansion, expansive; predict, predictable, prediction; circle, circular, circulation; prevent, prevention, preventive, deep, deeply, deepen, deepness; add, addition, additional, additionally; serious, seriousness, seriously; direct, directive, direction, directly; weak, weakly, weaken, weakness.

Exercise 9. Continue the raw of synonyms using the words from the text.

probable, possible; to restrict, to bound; forecast, prognosis; to effect, to induce; nearly, roughly; to deplete, to exhaust; area, district; in advance, beforehand; polar, north; to move, to travel; to come, to reach; to leave, go away.